Saliva

"Hah! Finally done..." Carl collapsed and stretched his entire body out on the ground. Between the brutal squats, pull-ups, and push-ups, he felt like he had just run through a war zone.

"Good work today. Here, take a water break and catch your breath," Diane said, tossing him a sealed bottle of cold water.

Gulp... gulp...

"Is this honestly your first time ever doing a serious workout? You're actually holding your own much better than most grown men out there, Carl," Diane remarked, stretching her arms above her head. Naturally, it had taken Carl nearly two grueling hours to finish every single set.

Because the system forced him to restart completely back to zero every single time his form slipped or he lost his grip on the pull-up bar, it had practically been a living hell.

"Hah... hah... is that supposed to be a compliment, Sister?"

"Of course it is! Now get up on your feet; we still need to start the endurance phase."